The need for a trusted accounting system
Sustainable Aviation Fuel (SAF) is crucial for reducing aviation's carbon footprint and is expected to account for 65% of emissions reductions by 2050. However, as of today, the supply of SAF is limited and not always available in locations where it is most needed. What can help to tackle this availability issue is splitting the SAF environmental attributes from the physical fuel so that airlines can claim the use of SAF even without physically transporting it. To be able to do that, the industry needs a trusted SAF accounting system that will transparently track and account for the SAF environmental attributes and the associated SAF claims while preventing SAF double-counting and double-claiming.
The SAF Registry meets these criteria and establishes a global, transparent, and liquid market for SAF which is critical for air transportation’s transition to net zero CO2 emissions by 2050. In essence, it functions as a chain of custody system, simplifying the administration and accounting of SAF environmental claims while safeguarding the strategic interests of airlines, meeting the needs of other SAF value chain stakeholders, and adhering to the GHG Protocol.
The Registry was developed in consultation with airlines, government authorities, OEMs, fuel producers and suppliers, and corporate travel management companies. With over 35 early users already in the process of onboarding and ready to use the system, the Registry is underpinned by the IATA SAF Accounting and Reporting Methodology, which provides a consistent approach to accounting for the environmental benefits of SAF purchases, regardless of location.
About the SAF Registry
The SAF Registry helps solve the challenge of limited SAF supply - which is acutely scarce and available in only a few locations globally – by connecting airlines with SAF producers and suppliers, while providing a Book & Claim solution, regardless of their geographical location. In addition, the Registry gives corporates access to in-sector emissions reductions, and capitalizes on firms’ capacity to co-finance the cost of decarbonization.
The SAF Registry is technology and feedstock neutral, favoring the emergence of diverse SAF production streams across the world. The Registry will be able to accommodate specific regulations, while favoring global harmonization. Moreover, interoperability with other registries is an important feature of the SAF Registry, favoring competition and open markets.
SAF Registry Features
- Follows the natural SAF value chain in accordance with the GHG Protocol philosophy: Scope 1 and Scope 3 emissions are properly aligned. SAF's environmental attributes are consistently and accurately accounted for throughout the entire value chain.
- Involves all SAF stakeholders, including airlines, States, producers, suppliers, intermediaries, and airline customers: Monitor and report SAF usage and emissions reductions effectively through a cohesive and streamlined process.
- Supports voluntary and regulatory reporting and claiming of SAF: Compliance with regulatory frameworks such as CORSIA and EU ETS. Ability to integrate future regulations.
- Enables Mass Balance SAF and Book & Claim Accounting: Flexible SAF accounting across the entire supply chain. Emissions reduction credited irrespective of the physical location of SAF.
- Ensures interoperability and avoids double issuance and claiming of SAF: Ensures data exchange with other registries, enhancing transparency and trust among stakeholders.
- Zero cost: The system will be free of charges to all users, until April 2027. It will then operate on a cost recovery basis.
How the SAF Registry works
The system conceptually has two distinct layers: Administration and Central Registry. In these two layers, users interact based on their role in the SAF value chain.
Figure: Conceptual overview: system layers (vertical) and system users and functions (horizontal)
- The Administration layer: serves as the facilitation level, offering non-transactional services such as registering and validating SAF batches, issuing SAF Fuel Units (SFUs), executing transfers of SFUs between users, facilitating the redemption of SFUs, onboarding and managing users, and supporting environmental reporting and regulatory compliance related to SAF.
- The Central Registry layer: includes two distinct accounting levels: a flexible (reversible) fuel level and a rigid (irreversible) emissions level.
- Fuel accounting level manages SFUs in fuel volume units, representing the total emissions reductions associated with the amount of SAF. Fuel producers, fuel suppliers, and aircraft operators have a transfer function that allows them to transfer SFUs within their inventories. Aircraft operators additionally have a redemption function, allowing them to irreversibly redeem SFUs to the emission accounting level, creating scope 1 and scope 3 emissions reductions.
- Emission accounting level generates stakeholder-specific emission statements and excerpts based on redeemed SFUs by the aircraft operator, providing evidence of emission reductions. Both emission excerpts and statements are facilitated by the administration layer.
The result is that the SAF Registry serves as the database for managing the chain of custody of environmental claims. It stores all relevant information for SFUs, including original Proof of Sustainability (PoS), issuances, transfers, and redemptions, which are logged and retained in the system indefinitely as evidence to be provided to authorities implementing regulatory schemes and auditors verifying voluntary carbon reduction claims.
About CADO
The Civil Aviation Decarbonization Organization (CADO) was created in March 2025 to maintain and operate the IATA-developed SAF Registry. It is a not-for-profit organization established under Canadian Law with its headquarters in Montreal.
CADO’s founding member is the International Air Transport Association (IATA) which provides ongoing technical and operational support for the SAF Registry. Membership in CADO is open to international organizations and companies in the SAF value chain.